Go to the "TicketPacks" directory and you should find a ticket pack for the map you're driving. Inside there will be an OTP file, which can be opened with a text editor like Notepad. At the top there will be a line [ticketpack]
, followed by 4 values. Those values are the probabilities for passengers using the ticket stamper, buying a ticket, chatting (saying hello or thank you) and complaining respectively. If you reduce the last to 0, they shouldn't complain.
Go to the "Vehicles" directory and find the directory for the bus you want to remove the rattles from. Inside the "Script" folder you should find a TXT file called "klappern_constfile". Change the value beneath klappern_faktor
to 0 and all the loose bits will go away.